1. Field of the Invention
This invention relates to a unidirectionally solidified anisotropic metallic composite body exhibiting transverse ductility, cyclic oxidation resistance, hot corrosion resistance and high temperature strength properties comprising a eutectic nickel-base superalloy containing about, on weight basis, 2-9% Re, less than about 0.8% Ti, at least 2% Mo, and less than 1% V. Embedded in the matrix is an aligned carbide reinforcing fibrous phase, preferably carbide(s) primarily of Ta.
2. Description of the Prior Art
Smashey's U.S. Pat. No. 3,904,402, issued Sept. 9, 1975 (filed June 1, 1973) broadly describes eutectic nickel-base alloys containing rhenium and a carbide reinforcing fiber phase exhibiting improved high temperature strength stress rupture properties. Smashey teaches the preferred use of 4-7% w/o vanadium for enhancement of carbide fiber as well as matrix strengthening. Smashey teaches the limited use of molybdenum, i.e. up to about 3% w/o, however preferably omits the use of Mo. Smashey also preferably limits tungsten to about 2-4 in nickel-base superalloys. Smashey summarily teaches the additive use of vanadium and the restrictive use of molybdenum and tungsten.
Recent studies of Smashey's alloys indicate that the alloys exhibit brittle (non-ductile) transverse strength properties as well as cyclic oxidation and hot corrosion limitations.